While adding some effects to a flex application, I noticed some strange behaviour. All of a sudden I noticed a function I had set to fire on the click event of a button was no longer firing.

I originally thought the effect intercepted the call in some way, but it turns out I had the effect set to fire on the mouseDownEffect. Changing the effect to fire on the mouseUpEffect brought the function back in to play.

A mouseDownEffect apparently changes the button before the click event fires. Hope this helps someone.